Imidazolium-based ionic liquids as co-surfactants in aqueous micellar two-phase systems composed of nonionic surfactants and their aptitude for recovery of natural colorants from fermented broth

•Control of the biomolecules partitioning using ILs as co-surfactants in AMTPs.•Imidazolium-based ILs and fermented broth increase the AMTPs’ cloud point temperature.•Increasing the colorants partitioning to the surfactant rich-phase with the addition of high ILs’ concentration.•Temperature strongly influences the partitioning of colorants in ILs-based AMPTs.•Higher temperatures enlarge the partitioning of red colorants into surfactant-rich phase.